The present invention relates to a magnetic detector, a coordinate input device and a magnetic image sensor using Matteucci effect.
When circumferential magnetization is provided to the interior of a single magnetic wire and external A.C. magnetic field is applied to the wire in the transverse direction thereof, a pulsative voltage is developed across the wire, that is, a so-called Mattecci effect takes place. Such Matteucci effect is known but its substantially no application techniques are known.
Further, as a digitizer or a coordinate input device for inputting handwritten letters, such a prior art device as shown in JP-A-61-70628 is known, but such a coordinate input device based on the aforementioned Matteucci effect is not known so far.
Meanwhile, a prior art magnetic image sensor for detecting magnetic data on a multi-track of a magnetic card or the like or a magnetic field caused by a magnetic material film uses a gap type magnetic head of multi-channel, a magnetic resistive element array, a Hall-effect element array, or the like. Thus, the prior art magnetic image sensor has been defective in that the magnetic image sensor is expensive and requires the number of detection circuits corresponding to the multi-channel and thus its necessary circuit is increased in size.